For this case we have that by definition, the area of a circle is given by:
[tex]A = \pi r ^ 2[/tex]
Where,
We have then that the radio is given by:
[tex]r = \frac {d} {2}[/tex]
Where,
Substituting values we have:
[tex]r = \frac {18} {2}\\r = 9[/tex]
Then, calculating the area we have:
[tex]A = \pi (9) ^ 2\\A = 81 \pi[/tex]
Answer:
on a circular serving tray that has a diameter of 18 in can be placed:
[tex]A = 81 \pi[/tex]
